To Wash Pots or Not

Friday, September 07, 2012

Picking Propagation Pots
My father believed in pruning paint and used it to coat every pruned branch that was bigger around than his finger. Even after well-documented research proved this practice unnecessary and in fact counterproductive, this educated man continued the folly. I swore I’d never be like that, never resist the inevitable changes that come to a vibrant world like Horticulture. Recently, I recalled Daddy’s spirited defense of his error when I found myself explaining why I still wash pots when I recycle them for propagation and other uses. All the authorities say the task is not needed unless the previous soil was contaminated or pest ridden, and then it is probably better to simply discard the pot. So, why do I persist? For that matter, why do we keep using round pots when square ones fit together so well and multiply the space for propagating? What’s up with our attitudes towards pots, and how do they affect cloning efforts?
An inveterate recycler, I seem incapable of tossing a perfectly good pot just because it has been used before. A stack of the same size pot can and often is right there, ready for use, but I must add recycles to it. They must be clean, years of science say, to prevent any lingering danger lurking on inside surfaces from reaching new plants. My reasoning adds that I can do without cross contamination from old pots to new ones and, after all, why not wash and disinfect the outside, too. There is no outdoor sink at our place, so pot washing is a laborious effort that involves 3 5 gallon buckets, soap, bleach, and heavy rubber gloves plus much bending over. Once the pots are cleaned with soap and water, rinsed, and rinsed again with a bleach solution, they have to dry. It’s hard to bribe anyone to towel the pots dry and common practice to set them out to dry. Even on benches, the pots can be knocked over by wind or dogs and I’ve always wondered if contact with the ground condemns them and me to a rewash. To do otherwise seems lazy.
After much reading and considering, count me in if it’s lazy to give up pot washing. I’m resolved to kick the habit because very few of my plants have pest issues. I am finally persuaded that chances of contamination in a small garden environment like mine are almost nonexistent. When it seems likely a plant died from root rot, I vow to toss both soil and container in the name of smart garden sanitation. I feel sure I will keep the used pots separated from the new ones, just in case.
A plant container can be anything so long as it can tolerate watering, hold soil in place, and provide drainage. Knowing that, people recycle most everything into pots, from egg cartons to liter bottles, plastic trays, and foam coolers. That’s fine, but their varied sizes make it tough to control the conditions so important to strong rooting. Sure, you can stick a jade plant cutting in a leaky old shoe full of damp sand, but if you want to root 10 jade plants or 100, set them up in pots the same size. If instead you fill a tray with assorted yogurt containers and plastic cups left over from a party, as I once did, bad things will happen. The pots’ different heights, depths, and drainage create assorted needs for watering which will drive you crazy and take away from the efficiency of your propagation space.
Similarly, the round shapes of such would-be rooting pots can be a geometric disaster in a small rooting area. Making a simple change to square pots can yield up to 3 times as many cuttings in the same space. Think about it this way: if rectangular parking spaces were circular, a row of ten spaces would become a row of 8 at best. It’s the same in a flat of pots set for cloning. It is also true that a rooting box can create even more usable rooting surface in the same size space. But I continue to use pots because I am not that good at slicing through the rooting media to separate the new clones. Professional growers tell me that if I’ll just be brave and use a sharp knife to slice right through, the roots will hardly be damaged at all. I know it’s true, but I cannot do it and fear that I will once again mutilate roots if I try. I’m beginning to have empathy for my father and his pruning paint. The way he did it worked, so why risk doing it another way?
Maybe I leaped into the future this summer by rooting tomato cuttings in a box of sand and a lightweight potting mix. I started them in June with great trepidation and six weeks later, slit through the mix and lifted the new transplants out with a spatula. They had plenty of roots but none had quite reached the edge of its space and thus there were no torn roots at all! I soaked the fresh cuttings in undiluted Hormex Liquid Concentrate for 5 minutes before I stuck them and watered the transplants in with a solution of 1T HLC/gallon of water. Not a day of wilt in the rooting bed or the garden, a combination of terrific HLC and personal pluck – I can do something differently!